I'm just getting into DnD, found this site, registered, and  then i figured it was possible to make your own creatures; and to cut things short, i love monsters, jumped on it, and made something incredibly imbalanced, and i now wish to remove it, or at least change it to make it better (And not be ashamed of it anymore). However it doesn't seem to be possible ? Am i just blind or is this...just not an option ?

You can "create a new version" that will overwrite the old one.

Not everything needs to be 'published' to the community.  Users are free to leave things as 'Private', which allow for personal/campaign use and open editing.

Thank you very much, this is extremely good to know.